Ab initio 13C and 19F NMR chemical shifts calculations for halogenated propanes

Abstract

Ab initio GIAO calculations were carried out on halogenated propanes, CClF 2–CF 2–CXYZ (X, Y, Z; H, Cl or F) and CF 3–CXY–CHCl 2 (X, Y; H, Cl or F), to estimate their 19F and 13C NMR chemical shifts values, considering all their rotamers. Although, the calculated values tend to be larger for the 19F NMR chemical shifts and smaller for the 13C NMR chemical shifts than the observed values, the calculated values show fairly good linear relationships with the observed values. The Hartree–Fock 6-31G(d) level of theory is of sufficient accuracy for application of assignment and prediction of 13C and 19F NMR chemical shifts of halogenated propanes.